132 



Mr. E. Schunck on the Colouring and 



[RecesSj 



In my earlier experiments, before I had commenced to employ ether 

 without alcohol for the separation of the two extractive matters, I occasion- 

 ally obtained mixtures of equal quantities of the two bodies, as proved by 

 several analyses of lead compounds, the results of which have been given, 

 For instance. Analyses I. Series A, and I. Series D, conducted to the for- 

 mula IT39 NO^Q. By doubling this formula, its. relation to the two other 

 formulae will be seen at once, since 



2(C,, H3, NO J = C,, II,, NO,, + C33 H,, N0,3. 



The Analysis I. Series B, which was made with a similar mixture, led to 

 the formula Cg, NO3-, which only differs from the preceding by three 

 equivalents of water, from which it is to be inferred that in this case also 

 both extractive matters were present, and that neither preponderated over 

 the other. These analyses, therefore, though valueless in themselves, 

 serve to confirm the two formulae given for the extractive matters. 



The extractive matter soluble in alcohol but insoluble in ether I pro- 

 pose to name urianine. The relation in which it may possibly stand to 

 urian is shown by the equation 



C,, NO,,+24 HO = C33 H,, NO,, + 4 (C, JI,, OJ, 



which proves that urian after absorbing water may split up into urianine 

 and glucose ; and though this is a process which I have not hitherto actu- 

 ally observed, still it is one which maybe assumed to take place within the 

 body. 



The later analyses of the lead compounds of this substance corresponded 

 with the formula C33 H^^ NOg,, as will be seen from the following Table, in 

 which the results are placed in juxtaposition with one another and with the 

 theoretical composition : — 





Calculation. 



F. TI. 



3. 



G. II. 



1, 2, 3. 



H. II. 

 2, 



H. III. 

 2. 



Mean. 



^38 • 



. 228 



43-42 



43-28 



43-59 



43-90 



43-33 



43-52 





. 27 



5-12 



5-69 



5-37 



5-15 



5-22 



5-37 



N . 



. 14 



2-66 



2-68 



2-34 



2-04 



2-52 



2-39 





. 256 



48-80 



48-35 



48-70 



48-91 



48-93 



48-72 





525 



100-00 



100-00 



100-00 



100-00 



100-00 



100-00 



The difference in composition to which the two formulee point is, in my 

 opinion, to be attributed not to any errors of analysis, nor to any variation 

 in the quality of the urine employed on difTercnt occasions, but rather to a 

 difference in the mode of preparation. In the later series of experiments 

 artificial heat was employed in the evaporation of the solutions instead of 

 the current of cold air made use of for the same purpose at the commence- 

 ment of the investigation. I am inclined to think that, in consequence of 

 the elevation of temperature, slight as it was, the substance took up four 

 equivalents of oxygen ; and though there was no apparent difference in the 

 physical properties of the original and the oxidized substance, still they can- 



